!> @file diffusion_w.f90
!------------------------------------------------------------------------------!
! This file is part of the PALM model system.
!
! PALM is free software: you can redistribute it and/or modify it under the
! terms of the GNU General Public License as published by the Free Software
! Foundation, either version 3 of the License, or (at your option) any later
! version.
!
! PALM is distributed in the hope that it will be useful, but WITHOUT ANY
! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
! A PARTICULAR PURPOSE. See the GNU General Public License for more details.
!
! You should have received a copy of the GNU General Public License along with
! PALM. If not, see .
!
! Copyright 1997-2018 Leibniz Universitaet Hannover
!------------------------------------------------------------------------------!
!
! Current revisions:
! -----------------
!
!
! Former revisions:
! -----------------
! $Id: diffusion_w.f90 3547 2018-11-21 13:21:24Z sward $
! variables documented
!
! 3241 2018-09-12 15:02:00Z raasch
! unused variables removed
!
! 2718 2018-01-02 08:49:38Z maronga
! Corrected "Former revisions" section
!
! 2696 2017-12-14 17:12:51Z kanani
! Change in file header (GPL part)
!
! 2233 2017-05-30 18:08:54Z suehring
!
! 2232 2017-05-30 17:47:52Z suehring
! Adjustments to new topography and surface concept
!
! 2118 2017-01-17 16:38:49Z raasch
! OpenACC version of subroutine removed
!
! 2037 2016-10-26 11:15:40Z knoop
! Anelastic approximation implemented
!
! 2000 2016-08-20 18:09:15Z knoop
! Forced header and separation lines into 80 columns
!
! 1873 2016-04-18 14:50:06Z maronga
! Module renamed (removed _mod)
!
! 1850 2016-04-08 13:29:27Z maronga
! Module renamed
!
! 1682 2015-10-07 23:56:08Z knoop
! Code annotations made doxygen readable
!
! 1374 2014-04-25 12:55:07Z raasch
! vsws + vswst removed from acc-present-list
!
! 1353 2014-04-08 15:21:23Z heinze
! REAL constants provided with KIND-attribute
!
! 1340 2014-03-25 19:45:13Z kanani
! REAL constants defined as wp-kind
!
! 1322 2014-03-20 16:38:49Z raasch
! REAL constants defined as wp-kind
!
! 1320 2014-03-20 08:40:49Z raasch
! ONLY-attribute added to USE-statements,
! kind-parameters added to all INTEGER and REAL declaration statements,
! kinds are defined in new module kinds,
! revision history before 2012 removed,
! comment fields (!:) to be used for variable explanations added to
! all variable declaration statements
!
! 1257 2013-11-08 15:18:40Z raasch
! openacc loop and loop vector clauses removed, declare create moved after
! the FORTRAN declaration statement
!
! 1128 2013-04-12 06:19:32Z raasch
! loop index bounds in accelerator version replaced by i_left, i_right, j_south,
! j_north
!
! 1036 2012-10-22 13:43:42Z raasch
! code put under GPL (PALM 3.9)
!
! 1015 2012-09-27 09:23:24Z raasch
! accelerator version (*_acc) added
!
! 1001 2012-09-13 14:08:46Z raasch
! arrays comunicated by module instead of parameter list
!
! 978 2012-08-09 08:28:32Z fricke
! outflow damping layer removed
! kmxm_x/_z and kmxp_x/_z change to kmxm and kmxp
! kmym_y/_z and kmyp_y/_z change to kmym and kmyp
!
! Revision 1.1 1997/09/12 06:24:11 raasch
! Initial revision
!
!
! Description:
! ------------
!> Diffusion term of the w-component
!------------------------------------------------------------------------------!
MODULE diffusion_w_mod
PRIVATE
PUBLIC diffusion_w
INTERFACE diffusion_w
MODULE PROCEDURE diffusion_w
MODULE PROCEDURE diffusion_w_ij
END INTERFACE diffusion_w
CONTAINS
!------------------------------------------------------------------------------!
! Description:
! ------------
!> Call for all grid points
!------------------------------------------------------------------------------!
SUBROUTINE diffusion_w
USE arrays_3d, &
ONLY : ddzu, ddzw, km, tend, u, v, w, drho_air_zw, rho_air
USE grid_variables, &
ONLY : ddx, ddy
USE indices, &
ONLY : nxl, nxr, nyn, nys, nzb, nzt, wall_flags_0
USE kinds
USE surface_mod, &
ONLY : surf_def_v, surf_lsm_v, surf_usm_v
IMPLICIT NONE
INTEGER(iwp) :: i !< running index x direction
INTEGER(iwp) :: j !< running index y direction
INTEGER(iwp) :: k !< running index z direction
INTEGER(iwp) :: l !< running index of surface type, south- or north-facing wall
INTEGER(iwp) :: m !< running index surface elements
INTEGER(iwp) :: surf_e !< End index of surface elements at (j,i)-gridpoint
INTEGER(iwp) :: surf_s !< Start index of surface elements at (j,i)-gridpoint
REAL(wp) :: flag !< flag to mask topography grid points
REAL(wp) :: kmxm !< diffusion coefficient on leftward side of the w-gridbox - interpolated onto xu-y grid
REAL(wp) :: kmxp ! end_index. Furtermore, note, no vertical natural surfaces
!-- so far.
!-- Default-type surfaces
DO l = 0, 1
surf_s = surf_def_v(l)%start_index(j,i)
surf_e = surf_def_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_def_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_def_v(l)%mom_flux_w(m) * ddy
ENDDO
ENDDO
!
!-- Natural-type surfaces
DO l = 0, 1
surf_s = surf_lsm_v(l)%start_index(j,i)
surf_e = surf_lsm_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_lsm_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_lsm_v(l)%mom_flux_w(m) * ddy
ENDDO
ENDDO
!
!-- Urban-type surfaces
DO l = 0, 1
surf_s = surf_usm_v(l)%start_index(j,i)
surf_e = surf_usm_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_usm_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_usm_v(l)%mom_flux_w(m) * ddy
ENDDO
ENDDO
!
!-- Add horizontal momentum flux u'w' at east- (l=2) and west-facing (l=3)
!-- surface.
!-- Default-type surfaces
DO l = 2, 3
surf_s = surf_def_v(l)%start_index(j,i)
surf_e = surf_def_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_def_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_def_v(l)%mom_flux_w(m) * ddx
ENDDO
ENDDO
!
!-- Natural-type surfaces
DO l = 2, 3
surf_s = surf_lsm_v(l)%start_index(j,i)
surf_e = surf_lsm_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_lsm_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_lsm_v(l)%mom_flux_w(m) * ddx
ENDDO
ENDDO
!
!-- Urban-type surfaces
DO l = 2, 3
surf_s = surf_usm_v(l)%start_index(j,i)
surf_e = surf_usm_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_usm_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_usm_v(l)%mom_flux_w(m) * ddx
ENDDO
ENDDO
ENDDO
ENDDO
END SUBROUTINE diffusion_w
!------------------------------------------------------------------------------!
! Description:
! ------------
!> Call for grid point i,j
!------------------------------------------------------------------------------!
SUBROUTINE diffusion_w_ij( i, j )
USE arrays_3d, &
ONLY : ddzu, ddzw, km, tend, u, v, w, drho_air_zw, rho_air
USE grid_variables, &
ONLY : ddx, ddy
USE indices, &
ONLY : nzb, nzt, wall_flags_0
USE kinds
USE surface_mod, &
ONLY : surf_def_v, surf_lsm_v, surf_usm_v
IMPLICIT NONE
INTEGER(iwp) :: i !< running index x direction
INTEGER(iwp) :: j !< running index y direction
INTEGER(iwp) :: k !< running index z direction
INTEGER(iwp) :: l !< running index of surface type, south- or north-facing wall
INTEGER(iwp) :: m !< running index surface elements
INTEGER(iwp) :: surf_e !< End index of surface elements at (j,i)-gridpoint
INTEGER(iwp) :: surf_s !< Start index of surface elements at (j,i)-gridpoint
REAL(wp) :: flag !< flag to mask topography grid points
REAL(wp) :: kmxm !< diffusion coefficient on leftward side of the w-gridbox - interpolated onto xu-y grid
REAL(wp) :: kmxp !< diffusion coefficient on rightward side of the w-gridbox - interpolated onto xu-y grid
REAL(wp) :: kmym !< diffusion coefficient on southward side of the w-gridbox - interpolated onto x-yv grid
REAL(wp) :: kmyp !< diffusion coefficient on northward side of the w-gridbox - interpolated onto x-yv grid
REAL(wp) :: mask_west !< flag to mask vertical wall west of the grid point
REAL(wp) :: mask_east !< flag to mask vertical wall east of the grid point
REAL(wp) :: mask_south !< flag to mask vertical wall south of the grid point
REAL(wp) :: mask_north !< flag to mask vertical wall north of the grid point
DO k = nzb+1, nzt-1
!
!-- Predetermine flag to mask topography and wall-bounded grid points.
flag = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_0(k,j,i), 3 ) )
mask_east = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_0(k,j,i+1), 3 ) )
mask_west = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_0(k,j,i-1), 3 ) )
mask_south = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_0(k,j-1,i), 3 ) )
mask_north = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_0(k,j+1,i), 3 ) )
!
!-- Interpolate eddy diffusivities on staggered gridpoints
kmxp = 0.25_wp * ( km(k,j,i)+km(k,j,i+1)+km(k+1,j,i)+km(k+1,j,i+1) )
kmxm = 0.25_wp * ( km(k,j,i)+km(k,j,i-1)+km(k+1,j,i)+km(k+1,j,i-1) )
kmyp = 0.25_wp * ( km(k,j,i)+km(k+1,j,i)+km(k,j+1,i)+km(k+1,j+1,i) )
kmym = 0.25_wp * ( km(k,j,i)+km(k+1,j,i)+km(k,j-1,i)+km(k+1,j-1,i) )
tend(k,j,i) = tend(k,j,i) &
+ ( mask_east * kmxp * ( &
( w(k,j,i+1) - w(k,j,i) ) * ddx &
+ ( u(k+1,j,i+1) - u(k,j,i+1) ) * ddzu(k+1) &
) &
- mask_west * kmxm * ( &
( w(k,j,i) - w(k,j,i-1) ) * ddx &
+ ( u(k+1,j,i) - u(k,j,i) ) * ddzu(k+1) &
) &
) * ddx * flag &
+ ( mask_north * kmyp * ( &
( w(k,j+1,i) - w(k,j,i) ) * ddy &
+ ( v(k+1,j+1,i) - v(k,j+1,i) ) * ddzu(k+1) &
) &
- mask_south * kmym * ( &
( w(k,j,i) - w(k,j-1,i) ) * ddy &
+ ( v(k+1,j,i) - v(k,j,i) ) * ddzu(k+1) &
) &
) * ddy * flag &
+ 2.0_wp * ( &
km(k+1,j,i) * ( w(k+1,j,i) - w(k,j,i) ) * ddzw(k+1) &
* rho_air(k+1) &
- km(k,j,i) * ( w(k,j,i) - w(k-1,j,i) ) * ddzw(k) &
* rho_air(k) &
) * ddzu(k+1) * drho_air_zw(k) * flag
ENDDO
!
!-- Add horizontal momentum flux v'w' at north- (l=0) and south-facing (l=1)
!-- surfaces. Note, in the the flat case, loops won't be entered as
!-- start_index > end_index. Furtermore, note, no vertical natural surfaces
!-- so far.
!-- Default-type surfaces
DO l = 0, 1
surf_s = surf_def_v(l)%start_index(j,i)
surf_e = surf_def_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_def_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_def_v(l)%mom_flux_w(m) * ddy
ENDDO
ENDDO
!
!-- Natural-type surfaces
DO l = 0, 1
surf_s = surf_lsm_v(l)%start_index(j,i)
surf_e = surf_lsm_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_lsm_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_lsm_v(l)%mom_flux_w(m) * ddy
ENDDO
ENDDO
!
!-- Urban-type surfaces
DO l = 0, 1
surf_s = surf_usm_v(l)%start_index(j,i)
surf_e = surf_usm_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_usm_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_usm_v(l)%mom_flux_w(m) * ddy
ENDDO
ENDDO
!
!-- Add horizontal momentum flux u'w' at east- (l=2) and west-facing (l=3)
!-- surfaces.
!-- Default-type surfaces
DO l = 2, 3
surf_s = surf_def_v(l)%start_index(j,i)
surf_e = surf_def_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_def_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_def_v(l)%mom_flux_w(m) * ddx
ENDDO
ENDDO
!
!-- Natural-type surfaces
DO l = 2, 3
surf_s = surf_lsm_v(l)%start_index(j,i)
surf_e = surf_lsm_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_lsm_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_lsm_v(l)%mom_flux_w(m) * ddx
ENDDO
ENDDO
!
!-- Urban-type surfaces
DO l = 2, 3
surf_s = surf_usm_v(l)%start_index(j,i)
surf_e = surf_usm_v(l)%end_index(j,i)
DO m = surf_s, surf_e
k = surf_usm_v(l)%k(m)
tend(k,j,i) = tend(k,j,i) + &
surf_usm_v(l)%mom_flux_w(m) * ddx
ENDDO
ENDDO
END SUBROUTINE diffusion_w_ij
END MODULE diffusion_w_mod